"I was very nervous about trying Implanon after reading all the negative reviews, but went ahead with it anyway.  The procedure was quick and practically painless.  The spot was tender for a few days and I did have an ugly bruise and now a tiny scar, but nothing that is too terrible.
I started Implanon while I was on my period, which lasted for about 21/2 weeks, give or take.  But the bleeding was minimal and it wasn't too bad.  Then after that period ended, nothing.  I haven't had a period since I had the device inserted in December of 09.  I haven't noticed any weight gain or unusual moodiness. This has been the best birth control I've ever been on.  My advice, give it a chance.  Don't let the negative reviews scare you away!"